The present invention relates to metallurgy and more specifically to metal cord steel used in the tire-making industry for reinforcing tires for ground wheels of motor vehicles and aircraft, and also used in other industrial rubber products.
Metal cord as rubber reinforcing material has gained wide application in many countries due to its higher strength, thermal stability and higher rigidity as compared with other materials used for the same purpose (glass-fiber cord, etc). Metal cord is actually a fabric reinforced with steel wire.
Widely known are steels for metal cord, comprising the following elements (in weight percent) as their main components: C 0.65-0.80, Mn 0.30-0.90, Si 0.15-0.40, P .ltoreq. 0.040, S&lt;0.040, and also Cr, Ni, Cu 0-0.10 (each).
Also known is the method of treating steels in the ladle by slag-forming mixture, with blowing them by inert gas for their purification of non-metal inclusions.
Quality of metal cord is determined principally by the properties of steel used for its manufacture - durability, strength and consistency of these properties.
Metal cord produced of known steels possesses insufficiently high flexural stability and fatigue strength, thus revealing one of the causes of rupturing metal cord failure in tires and premature ruining of tires.